Problems with fluorescent lighting

[Sheryl]

Before I start, let me preface this by saying I have no background in matters electric at all  so will appreciate if replies can  be really well spelled out and simple.  I know almost nothing about these things (which, as you will soon see, still puts me way ahead of the so-called "electricians" in my province).

 

My house, built in 1997, has fluorescent lights in the ceilings of each room.  Until about a year ago I got by quite happily with regular round fluorescent bulbs like this

 

 

And they lasted a long, long time (like, years)

 

About a year or two ago all the stores out my way (including Home Pro) completely stopped carrying this and instead had only these LED things with multiple tiny bulbs sort of like this

 

 

So I was forced to switch to these as the older ones burned out. Right away I found that this new type burned out really fast. A few months  and would need replacement, very annoying.

 

Then this week had to replace the one in my master bathroom. I don't remember exaclty but it had definitely been less than a year, and that light is not used much more than say an hour out of 24 hours each day.   Replaced it with the same wattage but as soon as replaced I found that (1) it flickers every couple of minutes or so in general and (2) it flickers wildly when I take a shower. Neither the water pump nor the to water heater are on the same circuit, they are each on their own circuits. Also, only the light in the bathroom flickers, not any of the other lights (as I would expect if the issue was the drop in voltage coming through wires due to the draw off from water pump and hot water heater......also, surely there should still be enough for a simple light fixture? No A/c running at same time. )

 

Attempted to get a diagnosis of the problem from local so-called electricians (and I do mean, so-called. First clue about these guys is their utter disinterest in knowing how to shut off the power before doing anything. In the past, they have caused electrical fires by putting in cables too small for the load onto the main power supply. You get the picture).  This resulted in them telling me the problem was that my hot water heater (stiebel-eltron) had something wrong with it  because it was drawing about 28 amps and "it should be 9 amps".  Actually per the specs anywhere from 8 - 36 A  is normal for this unit. He apparently based this on the labeling below, apparently taking the  kW to be the amperage.

 

Another "electrician" brought into the matter concurred and insisted that "all water heaters use 9 amps".  I quickly found that was completely untrue. Even the lower wattage ones use much more than that.

 

I considered the possibility that what he had measured at 28 was in fact kW not A (since he seems not to really know the difference) in which case there would indeed be a problem with the water heater,  but he was adamant that he measured A.  And also, if the problem was that the hot water heater was sucking up an inordinate amount of juice, surely more than that one light would be affected? And why the onset only after  that bulb was installed?

 

Maybe something is wrong with the wiring of that one fixture such that it is using way too much juice? If so what could it be? Already had it re-installed twice, no change.

 

One other thing as background, maybe relevant, maybe not: from the time the  house was first wired, all the fluorescent fixtures have glowed slightly when turned off (even if their circuits were turned off). Not for minutes but all night long, if anything more noticeable many hours later in the middle of the night. Locals of course claim this is totally normal and what they are supposed to do, even I know better than that. From past online consultations I gather it might be due to "reversed polarity" but I have not been able to confirm this. If it is that, it is true of every single light fixture in the house. Switching wires at the point of bulb installation makes no difference.  As I said, not sure if relevant.

 

I imagine next step needs to be measuring the voltage where the light fixture is.  I have a voltage meter, but neither I nor resident handyman knows how to use it (more exactly - how to read it. He knows how to use it to tell if a wire is live or not.)

 

It looks like this and I would greatly appreciate if someone could walk me through how to use and read it. I assume the setting at 250 ACV is correct? What is the black dial on the right for? And where among the many different lines should one read the voltage? Is it the red line labelled AC10V or where?

 

 

Also will greatly appreciate any thoughts about what may be going on.

 

Thanks in advance!!!

 

 

 

 

[Serenity_Now]

i cannot tell you how to use the meter
but maybe watching a you tube video might be the thing to do

it may be easier than someone trying to explain it.

as far as the lights go I have seen the orange glow many many times 
could be that its not earthed but really who knows 
as far as the led strips go
they are basically just crap
there is usually a convertor box attached to these and they are the cheapest crap
but the problem would be reversed wiring and no proper earth at the light holder 
please see page two od a very similar problem actually the same 
its an easy read through


click her i could not post the link directly

 

 

[a3tsw]

Hi ,

Plenty of the old style circular fluorescent bulbs available on Lazada.

 

[Serenity_Now]

4 minutes ago, a3tsw said:

Hi ,

Plenty of the old style circular fluorescent bulbs available on Lazada.

that would be the way to go if you were happy with them but check the wiring is the right way round as displayed in the link

 

11 minutes ago, Serenity_Now said:

click her i could not post the link directly

 

[brianthainess]

40 minutes ago, Sheryl said:

Before I start, let me preface this by saying I have no background in matters electric at all  so will appreciate if replies can  be really well spelled out and simple.  I know almost nothing about these things (which, as you will soon see, still puts me way ahead of the so-called "electricians" in my province).

 

My house, built in 1997, has fluorescent lights in the ceilings of each room.  Until about a year ago I got by quite happily with regular round fluorescent bulbs like this

 

 

And they lasted a long, long time (like, years)

 

About a year or two ago all the stores out my way (including Home Pro) completely stopped carrying this and instead had only these LED things with multiple tiny bulbs sort of like this

 

 

So I was forced to switch to these as the older ones burned out. Right away I found that this new type burned out really fast. A few months  and would need replacement, very annoying.

 

Then this week had to replace the one in my master bathroom. I don't remember exaclty but it had definitely been less than a year, and that light is not used much more than say an hour out of 24 hours each day.   Replaced it with the same wattage but as soon as replaced I found that (1) it flickers every couple of minutes or so in general and (2) it flickers wildly when I take a shower. Neither the water pump nor the to water heater are on the same circuit, they are each on their own circuits. Also, only the light in the bathroom flickers, not any of the other lights (as I would expect if the issue was the drop in voltage coming through wires due to the draw off from water pump and hot water heater......also, surely there should still be enough for a simple light fixture? No A/c running at same time. )

 

Attempted to get a diagnosis of the problem from local so-called electricians (and I do mean, so-called. First clue about these guys is their utter disinterest in knowing how to shut off the power before doing anything. In the past, they have caused electrical fires by putting in cables too small for the load onto the main power supply. You get the picture).  This resulted in them telling me the problem was that my hot water heater (stiebel-eltron) had something wrong with it  because it was drawing about 28 amps and "it should be 9 amps".  Actually per the specs anywhere from 8 - 36 A  is normal for this unit. He apparently based this on the labeling below, apparently taking the  kW to be the amperage.

 

Another "electrician" brought into the matter concurred and insisted that "all water heaters use 9 amps".  I quickly found that was completely untrue. Even the lower wattage ones use much more than that.

 

I considered the possibility that what he had measured at 28 was in fact kW not A (since he seems not to really know the difference) in which case there would indeed be a problem with the water heater,  but he was adamant that he measured A.  And also, if the problem was that the hot water heater was sucking up an inordinate amount of juice, surely more than that one light would be affected? And why the onset only after  that bulb was installed?

 

Maybe something is wrong with the wiring of that one fixture such that it is using way too much juice? If so what could it be? Already had it re-installed twice, no change.

 

One other thing as background, maybe relevant, maybe not: from the time the  house was first wired, all the fluorescent fixtures have glowed slightly when turned off (even if their circuits were turned off). Not for minutes but all night long, if anything more noticeable many hours later in the middle of the night. Locals of course claim this is totally normal and what they are supposed to do, even I know better than that. From past online consultations I gather it might be due to "reversed polarity" but I have not been able to confirm this. If it is that, it is true of every single light fixture in the house. Switching wires at the point of bulb installation makes no difference.  As I said, not sure if relevant.

 

I imagine next step needs to be measuring the voltage where the light fixture is.  I have a voltage meter, but neither I nor resident handyman knows how to use it (more exactly - how to read it. He knows how to use it to tell if a wire is live or not.)

 

It looks like this and I would greatly appreciate if someone could walk me through how to use and read it. I assume the setting at 250 ACV is correct? What is the black dial on the right for? And where among the many different lines should one read the voltage? Is it the red line labelled AC10V or where?

 

 

Also will greatly appreciate any thoughts about what may be going on.

 

Thanks in advance!!!

Yes Set the meter to the red Zone ACV at 250V but need to see the inlets for the test leads.

Try not to get electrocuted please. 

Having said that I think I have seen the old Fluro type for sale in 7/11 and Mini C. 

[Etaoin Shrdlu]

I think it might be the way the switch is wired. If the switch disconnects the neutral wire and not the phase, you could have this problem.

[MangoKorat]

To check the voltage, yes you are using the correct scale DCV250 & ACV250.  That scale will read AC voltage up to 250v. Read the voltage registered on that scale. In a Thai domestic situation you should be getting 220 to 230v.  However, there are often large variations in Thailand - mostly on the low side. The voltage can drop quite a lot before you'd actually notice in on the lights.

 

The 10V scale is for checking lower voltages more acurrately - its hard to see low voltages on the larger black scale.

 

The black dial is for you to zero the needle - through different types of usage, the needle might not stast where it should.  Turn the dial whichever way - to locate the pointer to zero before taking a reading.

 

 

Edited February 23 by MangoKorat

[MangoKorat]

Sorry, on a second look - use the scale (red) that says AC10V but set the meter to 250.

 

I have to say that's probably the most confusingly scaled meter I've seen.

[MangoKorat]

I'm no electrician - hopefully Crossy will be along soon and give you some advice.

 

However,  Thai' electricians', I use the term lightly, wire houses up very differently to what is generally accepted in other parts of the world.  There is rarely any separate lighting, sockets and high ampage circuits.

 

I suspect that your problem is something to do with the water heater and its shorting the live across to the neutral. You might think the lights are on a separate circuit but I doubt the neutrals are separate - hence a neutral fault can give problems in other areas. In my house the lights take their positive from the socket supply in the same room and they all both share the neutrals.

 

Such a fault should flip the trips in your consumer unit - provided of course, that trip has been wired correctly in the first place.  Connecting the outgoing live to the incoming live renders the trip completely useless yet that was how a house I rented was wired!

 

I've also found that some Thai fittings and switches 'leak' electricity - I've had readings of 2 to 12v on the plastic parts of a light switch - cured by replacing the switch. I've changed all my sockets to UK ones now but I previously also had a Thai double socket reading around 50v on the plastic!

 

Anyway, electric is a strange beast and I'm just speculating.  Hopefully someone with real electrical experience will be able to point you in the right direction

[GammaGlobulin]

I actually have TWO of the same power Stiebel water heaters.

Or, mine is rated at 8000 watts.

These hot water heaters will draw about 37 AMPS with the voltage supplied in Thailand.

 

When you first turn on the water heater, it will draw slightly more AMPS.

But very quickly, the voltage drops from 220 to about 200 or so.

And the AMPs goes down to about 37.

 

This type of machine requires a 40 AMP circuit breaker.

 

Also, if you contact Stiebel, they will send out their company technician to check everything for about Bt.500, judging by my experience in CM.

 

Stiebel is a very good company, I think.

 

(I have TWO DHC 8 XG machines. They are great.  These machines allow for fine graduated water temperature control.  I doubt there is anything wrong with these machines.  And, if you want to check, then just contact STIEBEL for a company man to come to inspect.  They know what they are doing.  Smart guys in CM>)

 

 

 

 

Edited February 23 by GammaGlobulin

[Banana7]

Use ohms's law to calculate amperage. See https://en.wikipedia.org/wiki/Ohm's_law : v=IR; where V= voltage, I = is current, and R is resistance

Basically, take watts  divide by voltage to determine amps.

 

If the voltage is 220 to 240AC, and most electricity delivered to consumers is in this range in Thailand, 28 amps may be okay but not for shower water heater. It seems this water heater is for the whole house, and can draw up to 40A.

Edited February 23 by Banana7

[Sheryl]

15 minutes ago, GammaGlobulin said:

I actually have TWO of the same power Stiebel water heaters.

Or, mine is rated at 8000 watts.

These hot water heaters will draw about 37 AMPS with the voltage supplied in Thailand.

 

When you first turn on the water heater, it will draw slightly more AMPS.

But very quickly, the voltage drops from 220 to about 200 or so.

And the AMPs goes down to about 37.

 

This type of machine requires a 40 AMP circuit breaker.

 

Also, if you contact Stiebel, they will send out their company technician to check everything for about Bt.500, judging by my experience in CM.

 

Stiebel is a very good company, I think.

 

(I have TWO DHC 8 XG machines. They are great.  These machines allow for fine graduated water temperature control.  I doubt there is anything wrong with these machines.  And, if you want to check, then just contact STIEBEL for a company man to come to inspect.  They know what they are doing.  Smart guys in CM>)

 

 

 

 

It would cost me quite a lot to have them vome out since I live ipcountry and they would have to vome from Bangkok.

 

I would certainly still do it if I thought the hot water heater was the problem but I really doubt it because:

 

- installed by Stiebel not l8cals

-working fine, no issues with its function. Problem is solely in nearby light fixture and there, only after new bulb installed. 

[Sheryl]

17 minutes ago, Banana7 said:

Use ohms's law to calculate amperage. See https://en.wikipedia.org/wiki/Ohm's_law : v=IR; where V= voltage, I = is current, and R is resistance

Basically, take watts  divide by voltage to determine amps.

 

If the voltage is 220 to 240AC, and most electricity delivered to consumers is in this range in Thailand, 28 amps may be okay but not for shower water heater. It seems this water heater is for the whole house, and can draw up to 40A.

As mentioned the manufacturer specs state 8 - 36 amps.

 

It is installed only in 1 bathroom. I know it is more power than would need for shower only but I like to take baths.

 

Anyway chouce of water heater is not the issue. I've had it for 7 years and it suits my needs and still works fine. Issue is in nearby (but on  separate circuit) light fixture and started only after new bulb change. 

[Sheryl]

40 minutes ago, MangoKorat said:

 

I suspect that your problem is something to do with the water heater and its shorting the live across to the neutral. You might think the lights are on a separate circuit but I doubt the neutrals are separate - hence a neutral fault can give problems in other areas. In my house the lights take their positive from the socket supply in the same room and they all both share the neutrals.

 

Interesting.  Could this be due to something wrong in the light fixture due somehow to how the new light  bulb was installed? (As problem only started then). Or does it have to be from a problem in the water heater itself? (Which seems to work fine). I ask because have to decide whether to invest in having Stiebel send out technician from Bangkok (very costly as 6 hour r/t drive -- I'll certainly do it if indicated but hate to waste my money and their time if the issue is in the light fixture. ). 

[Sheryl]

1 hour ago, Etaoin Shrdlu said:

I think it might be the way the switch is wired. If the switch disconnects the neutral wire and not the phase, you could have this problem.

How could I check this? Handyman did mention something about the switch feeling hot.....

 

But when switch is on how why would this matter?  Or were you referring to the afterglow rather than the flickering while turned on? 

[GammaGlobulin]

24 minutes ago, Sheryl said:

It would cost me quite a lot to have them vome out since I live ipcountry and they would have to vome from Bangkok.

 

I would certainly still do it if I thought the hot water heater was the problem but I really doubt it because:

 

- installed by Stiebel not l8cals

-working fine, no issues with its function. Problem is solely in nearby light fixture and there, only after new bulb installed. 

 

a.  I agree that it is unlikely that the Stiebel machine is the culprit. (Several times in the past, when I had electrical problems in the house, the local electricians were very quick to blame my Stiebel machines.  BUT, in every case, the problems involved faulty wiring, done by the local electricians.)

 

b. I live in CM.  However, wherever you are, then you might just place a call to Stiebel, in case you want to have the machine checked for any potential problem. It cots nothing to ask Stiebel.  And, who knows, you might end up being pleasantly surprised; they provide excellent service.  And they just might have a company technician that could stop by your locale when visiting other customers.  I would definitely give it a try.  Normally, the set fee from Stiebel is BAHT500 per service call. Or, this is what it is outside of CM.  And, they are extremely prompt if, for any reason, the machine stops working, even if the problem might not be due to the Stiebel machine.

 

 c.  Although it's a matter of personal preference, I, personally, detest fluorescent lighting in the house. Instead of those fluorescent light "rings", I detached those and installed single bulbs, some Panasonic florescent soft warm bulbs, or those LED bulbs (single bulbs), in warm white, or soft white, depending upon the brand.

 

d.  If you have an electrical wiring problem in the ceiling wiring to the lighting fixtures, then maybe this would be an excuse to improve the types of lights being used, according to personal preference.

 

(sorry if this might not be as helpful as I had hoped...)

 

 

Further Note:  The recessed ceiling-light socket/housings that fit up into the ceiling, which are designed for a single bulb, are quite inexpensive...and look quite nice.  (Comfortable Lighting is important for wellbeing, IMHO...)

 

 

 

Edited February 23 by GammaGlobulin

[Denim]

Totally different experience.  Our house was built 8 years ago and we started off with round fluorescence lights.

 

OK but not very bright. Our electrician advised we change to the round LED lights as use less power and a bit brighter.

 

Only 1 out 4 has died in 4 years of use plus I like the fact no starter is needed so no flickering. Also cooler than fluorescent  light.

 

 

[Etaoin Shrdlu]

9 minutes ago, Sheryl said:

How could I check this? Handyman did mention something about the switch feeling hot.....

 

But when switch is on how why would this matter?  Or were you referring to the afterglow rather than the flickering while turned on? 

The glowing lights after the switch is turned off.

[Serenity_Now]

9 minutes ago, Sheryl said:

How could I check this? Handyman did mention something about the switch feeling hot.....

 

But when switch is on how why would this matter?  Or were you referring to the afterglow rather than the flickering while turned on? 

turn of the power open switch 
swap the wires around 
could be its your switch is switching the neutral, not the live.
as you have no fluros you cant tell but a fluro will no longer glo

[observer90210]

I had problems in the ceiling recessed lights with dimmer,  that started to flicker suddenly when light was left on low light. 

 

Same story with all the electric cowboys who could never really explain.

 

Plainly changed the brand of the bulbs and till now, no more issues.

 

If the lights have dimmer switch fixed on the main laines, they may/can have issues as the switches apparently in Thailand may not be able to handle it no matter what. 

 

But this is plainly a guess as once again, I am absolutely no specialist in the matter. Just that in my case it was solved (for the moment), in changing the brand of the led bulbs.

[Sheryl]

2 minutes ago, Etaoin Shrdlu said:

The glowing lights after the switch is turned off.

Ok thanks. This is not the immediate ptoblem, I only mentioned it as background in  case relevant. Probably shouldn't have as it seems to have distracted people.

 

You may well be right about it's cause though, makes sense . 

[MangoKorat]

21 minutes ago, Sheryl said:

Interesting.  Could this be due to something wrong in the light fixture due somehow to how the new light  bulb was installed? (As problem only started then). Or does it have to be from a problem in the water heater itself? (Which seems to work fine). I ask because have to decide whether to invest in having Stiebel send out technician from Bangkok (very costly as 6 hour r/t drive -- I'll certainly do it if indicated but hate to waste my money and their time if the issue is in the light fixture. ). 

It could be so many things Sheryl to be honest.  A decent electrician should find it easily.  I found a 'real' electrician by quietly asking if anyone did 'moonlights' at my local PEA office.

Edited February 23 by MangoKorat

[Sheryl]

6 minutes ago, Serenity_Now said:

turn of the power open switch 
swap the wires around 
could be its your switch is switching the neutral, not the live.
as you have no fluros you cant tell but a fluro will no longer glo

Sorry I don't follow.

 

I do have fluorescent lights and  specifically  one of them flickers wildly when I take a shower. Started only after bulb replaced (tho prior bulb burned out quicker than it should have).

 

The glowing bit was mentioned only as background in case relevant and is not the immediate problem. 

[Dan O]

48 minutes ago, Sheryl said:

Ok thanks. This is not the immediate ptoblem, I only mentioned it as background in  case relevant. Probably shouldn't have as it seems to have distracted people.

 

You may well be right about it's cause though, makes sense . 

You may have a couple different issues here.

 

The flicker in the led circle could be just a low quality bulb string.  Swap it with a same bulb from somewhere else in you house and see if the current one still flickers but the swapped one works ok in the bath. It can also be caused by a loose wiring connection, I believe you said you had changed out the fixtures to these led rings. 

 

As for the continued glow after turning off the lights is due to electrical leakage in the wiring, probably a junction box causes this. It doesnt take much leakage into the line to cause this. 

 

The wiring to your bath fixture shouldn't be affected by the water heater so forget about worrying about that being the cause. 

[Serenity_Now]

46 minutes ago, Sheryl said:

I do have fluorescent lights and  specifically  one of them flickers wildly when I take a shower. Started only after bulb replaced (tho prior bulb burned out quicker than it should have).

sorry to joke but at that point i would be worried about taking a shower

besides that if the switch is flipping neutral instead of live that would be the heat build up and the afterglo (glos not the issue but its a clue the glo would indicate reversed wiring)

plus even if you switch the wires at the fitting it is still running through a smaller pathway on the switch 
heat build up maybe a short but the last bulb blew now you have a flicker
forget about the heater

sort out the switch and dble check the light fitting 

then any other room that gives you the after glo sort the wiring
bathroom is just been the first to go your adding steam and condensation into the mix
or find the resident expert Crossy


 

[NoDisplayName]

Multimeters aren't terribly expensive.  You might want to buy a new one with digital readout.

 

Are you cutting power at the main breaker or the light switch when you're fiddling with your wires?  Could be the installer put the fixture upstream of the switch.  Live goes into the light, then the switch is on the neutral.  That breaks the circuit, but there's still always juice at the light.  You have an LED voltage pencil tester?

[ravip]

I assume the setting at 250 ACV is correct? - Yes

 

And where among the many different lines should one read the voltage? Is it the red line labelled AC10V or where? - Yes

 

What is the black dial on the right for? - If you are referring to the X1 X10 X100 - that's the ohms scale.  The meter should NEVER be connected to a powered circuit when on this scale. This can be used to test a broken wire, burnt out fuse, an incandescent light bulb to mention a very few simple examples.

 

from the time the  house was first wired, all the fluorescent fixtures have glowed slightly - might be due to a faulty ground.

 

But lets wait for the expert, Crossy. 

 

[Sheryl]

16 minutes ago, Dan O said:

You may have a couple different issues here.

 

The flicker in the led circle could be just a low quality bulb string.  Swap it with a same bulb from somewhere else in you house and see if the current one still flickers but the swapped one works ok in the bath. It can also be caused by a loose wiring connection, I believe you said you had changed out the fixtures to these led rings. 

 

As for the continued glow after turning off the lights is due to electrical leakage in the wiring, probably a junction box causes this. It doesnt take much leakage into the line to cause this. 

 

The wiring to your bath fixture shouldn't be affected by the water heater so forget about worrying about that being the cause. 

Thank you. I will try the bulb switch tomorrow as a first step... Don't know  why I didn't think of it!! Stay tuned and I'll post the results tomorrow.

 

I too thought the afterglow must mean electrical leakage since  even turning off the circuits doesn't stop it.  But I am not clear what you mean by a "junction box"? Is it the same as the fuse box? If so, what would cause leakage there/ how to confirm it/ what can be done about it?

[Sheryl]

10 minutes ago, ravip said:

 

What is the black dial on the right for? - If you are referring to the X1 X10 X100 - that's the ohms scale.  The meter should NEVER be connected to a powered circuit when on this scale. This can be used to test a broken wire, burnt out fuse, an incandescent light bulb to mention a very few simple examples.

 No not that.Small black knob above and to the right of the  main settings.  It says above it O followed by a symbol  then ADJ. Someone else said it is for calibrating/xeroing the meter.

[Sheryl]

27 minutes ago, Serenity_Now said:

sorry to joke but at that point i would be worried about taking a shower

besides that if the switch is flipping neutral instead of live that would be the heat build up and the afterglo (glos not the issue but its a clue the glo would indicate reversed wiring)

plus even if you switch the wires at the fitting it is still running through a smaller pathway on the switch 
heat build up maybe a short but the last bulb blew now you have a flicker
forget about the heater

sort out the switch and dble check the light fitting 

then any other room that gives you the after glo sort the wiring
bathroom is just been the first to go your adding steam and condensation into the mix
or find the resident expert Crossy


 

OK, several folks now have said the problem maybe that the switch is wired with neutral instead of live.  How should that be tested for? Touch the voltmeter to the wire the switch is on? If it is neutral would that then show no juice or low juice??